Neigh: Journal retracts brief endangered horse paper for mysterious reasons

Is retracting a paper like shutting the barn door after the horses have bolted?

Sadly, that’s a more apt metaphor than we’d like for a retraction in Equine Veterinary Journal of a short paper about efforts to save Przewalski’s horses, an endangered species closely related to domestic horses. Here’s the notice:

The following article from Equine Veterinary Journal, ‘Przewalski’s Horses in Western China: When will reintroduction succeed?’ by X. Sheng, H. Zhang, Q. Weng, G. Watanabe and K. Taya , published online on 21 September 2011 in Wiley Online Library (http://onlinelibrary.wiley.com), has been retracted by agreement between the authors, the journal Editor in Chief, Celia M Marr and Blackwell Publishing Ltd. The retraction has been agreed due to the identification of several errors and inaccuracies in the information presented in the article.

“Several errors and inaccuracies” seemed like a lot in a six-paragraph paper, so we tried to reach the editor of the journal, and the corresponding author, for more details. We’ll update with anything we hear back.

In the meantime, we wanted to know more about Przewalski’s horses, and we turned to a Retraction Watch reader who knows equines, Elizabeth Gormley. She pointed us to a number of resources, including a Food and Agriculture Organization (FAO) site featuring these key quotes:

The Asian wild horse, known as Equus przewalskii and named after N.M. Przewalski, explorer of Central Asia, earlier populated a vast territory of Asian steppes, stretching from the Kazakh area to the piedmonts of Tien Shan and the Mongolian Altai.

At present, the representatives of this species can be seen only in the zoos and reserves of the world. The total captive population of the wild horse derives from 12 wild horses, imported from Dzungaria into Europe at different times and one domestic mare.

All this points to the fact that only one stallion is used for breeding in these zoos. Not a single zoo in the world uses its capabilities to the full extent. As a result, homozygosity is increasing and the gene pool is being depleted in the isolated groups of horses, and it affects their reproduction abilities and viability.

 A 2011 paper in Genome Biology and Evolution reported on a genetic analysis of the species:

The endangered Przewalski’s horse is the closest relative of the domestic horse and is the only true wild horse species surviving today. The question of whether Przewalski’s horse is the direct progenitor of domestic horse has been hotly debated.

However, the authors conclude:

Our results suggest that Przewalski’s horses have ancient origins and are not the direct progenitors of domestic horses.

Gormley told us:

This is an important area of scientific study, because Przewalski’s horses are becoming more prone to illness and have lost some abilities that previous generations of these horses had. This is one reason why the genetics of equine adaptations are important areas of study. Apparently horses died during previous reintroductions.

From the FAO site:

Overall, it can be said that this species has lost a number of features that allowed the wild horse in the past to withstand the severe environmental conditions of Central Asia. This refers both to the phenotype and genotype features, taking into account the growing homozygosity and the loss of gene pool variability. Since the factors that cause such phenomena are still existing these processes continue to develop and the captive evolution of the species continues. That is why there is a possibility to have another species under the name of Equus przewalskii Pol. tomorrow! As we see it, the perspectives for the future survival of this species in captivity, under conditions totally different from the natural environment, are not very bright. In the future we will face further domestication and the loss of variability of the gene pool that is in full contradiction with the objectives of preserving that species. The world scientists display permanent concern over the fate of Equus przewalskii as a species. The resolutions of all international symposia on the survival of Equus przewalskii stress that captive reproduction does not guarantee the preservation of the diverse gene pool. The most radical measure of saving that species will be the wild horse introduction into the natural biotopes and creation of a big population in nature. The return of the horses to the natural steppe biotopes will not only ensure the preservation of their gene pool, genetic type, and the follow-up natural evolution, but will enrich the natural communities and will become a model for the preservation of other types that will give a powerful impetus to world environmental activities.

You can read up-to-date recommendations from the International Union for Conservation of Nature here and a piece on a trip to the Gobi Desert to see the horses by Greg Breining here.

Hat tip: “Clare Francis”